Certain applications, such as computing and wireless communication devices, require bipolar complementary metal-oxide semiconductor (BiCMOS) integrated circuits. These applications require a low-noise amplifier (LNA) device and a power amplifier (PA) device, e.g., SiGe heterojunction bipolar transistors (HBTs) integrated on the same wafer.
However, the LNA device and the PA device can have different performance and optimization requirements. For example, the LNA device may require a relatively high beta, a relatively high short circuit current gain cut-off frequency (fT) and a relatively low base resistor (Rb). On the other hand, the PA device may require a relatively low base emitter capacitance (Cbe) and a relatively high breakdown voltage (BVceo) (nominal Beta).
It is possible to have the LNA device and the PA device HBTs share a same base profile. However, in such an approach only one device can be optimized for performance while the other device is optimized for the given base profile using either extra implants or layouts.